FRESNO, Calif. (KFSN) -- An internal investigation is underway at the Madera County Jail after authorities say a gang-related fight involving 11 inmates resulted in a lockdown. The fight was originally reported to the Madera County Sheriff's Office as an attempted takeover by inmates.

The Madera County Department of Corrections said 11 inmates were involved in a gang on gang assault in the maximum security housing unit. During the fight, other inmates tried breaking the security glass so they could get involved in the fight. Their efforts were unsuccessful and officers were able to eventually control the situation.

Madera County Supervisor David Rogers says realignment from prisons to reduce overcrowding has resulted in a violent inmate population in county jails.

Rogers said, "These people are more sophisticated criminals they are looking for ways to cause trouble. They are trouble makers. And that's why they were in state pen."

The corrections department said no staff members were injured in the incident and inmates only sustained superficial injuries. Those inmates were treated by medical staff at the jail. The jail sustained moderate damage, including broken security glass and security door.

BREAKING UPDATE: @MaderaSheriff now says there was a 'fight between inmates' at the jail, not the 'attempted takeover' initially confirmed.